#5. Nuclear War
Risk of Extinction: 1%
During the Cuban missile crisis, President John F. Kennedy estimated the odds of global nuclear war at one in three. Thankfully, the odds are no longer even remotely that dire. But still, the risk remains. With around 20,000 nuclear weapons stockpiled worldwide, there persists plenty of firepower to spoil the planet, and possibly send the human race spiraling towards extinction. To set such a chain of events in motion, it only takes one mistake. According to Joseph Cirincione, that almost happened in 1995:
"Russian military officials mistook a Norwegian weather rocket for a US submarine- launched ballistic missile. Boris Yelstin became the first Russian president to ever have the ‘nuclear suitcase’ open in front of him. He had just a few minutes to decide if he should push the button that would launch a barrage of nuclear missiles. Thankfully, he concluded that his radars were in error. The suitcase was closed."
(Image: Wikimedia Commons)